____________________________________________________________________________________ 
____________________________________________________________________________________ 
26  NTU Optical Network Terminals 
3.2 NTU-2W Architecture 
 
Fig. 15— Logical Architecture of a Device with Factory Settings 
Main Components of the Device: 
–  optical receiver/transmitter (SFF module) for conversion of an optical signal into an electric one; 
–  processor (PON chip) which converts Ethernet and GPON interfaces. 
A device with factory (initial) settings have the following logical blocks (see Fig.15Fig. 15):  
  br1; 
  eth0…1; 
  wl0; 
  IPInterface. 
In this case, the br1 block is used to combine LAN ports in one group. 
The eth0..1 blocks physically represent Ethernet ports with RJ-45 connector for connection of PC, STB, or 
other network devices. They are logically included into the br1 block.  
The wl0 block is an interface for Wi-Fi module connection. 
The Filter and Marking blocks are designed to include local interfaces in one group (br1). These blocks are 
responsible for traffic rules: Filter is used for incoming traffic, while Marking—for the outgoing one. 
The  IPInterface  block  is  a  logical  object  with  an  IP  address  for  LAN  access  and  a  DHCP  server,  which 
assigns addresses to clients. 
A  connection  to  the  OB  device  (successful  connection  to  a  stationary  OLT)  additionally  creates  the 
gpondef blocks with the help of the OMCI protocol (ONT Management and Control Interface). The block ensures 
connection of the subscriber’s ONT device to station-side equipment.